"We’ve long admired Jamestown Associates for their creativity, winning record in tough campaigns, and the quality of their product," Club for Growth President Chris Chocola said in a statement on Friday. "When we heard recently that they would have more time to work with Club for Growth Action we immediately seized the opportunity. We look forward to the opportunity to utilize their services on races like Chris McDaniel’s in Mississippi and Ben Sasse’s in Nebraska."

The hiring of the consulting group is a clear show of defiance toward establishment Republicans who have tried to use Jamestown as an example of what happens to organizations involved in trying to defeat incumbent Republican lawmakers.

The mention of Sasse in particular is significant. In 2013 Senate Minority Leader Mitch McConnell (R-KY), the primary target of these outside groups, sat down with Sasse and scolded him for allowing outside groups to work with him.

Jamestown has long been the subject of controversy. Besides defying establishment Republicans over the past few years it caught flack in 2010 making a casting call seeking for "hicky" looking actors to star in an ad for a West Virginia Senate race.